Many kinds of needle protection devices are available for providing post injection needle stick protection. Needle stick protection is especially significant to health care professionals presently because of the prevalence of potentially fatal infectious diseases, such as AIDS, that can be transmitted to health care workers by inadvertent jabs from a needle subsequent to its use in an infected patient.
Common types of needle stick protection devices include sheath type protectors such as those disclosed in U.S. Pat. Nos. 4,725,267 and 4,804,371 to Vaillancourt. Sheath type protectors fully encompass the needle with a cap or end portion which may be actuated along the length of the needle to cover the sharp injecting end portion. Spring biasing may be used to effect the actuation or extension. Typically, sheath type protectors have material which extends the full length of the hypodermic needle. Provision of such amounts of material on long hypodermic needles adds considerable bulk and cost to the needle.
Another type of protective enclosure for a hypodermic needle is disclosed in U.S. Pat. No. 4,735,618 to Hagen. Hagen discloses an enclosure formed by a tubular sleeve sized for friction engagement over the barrel portion of a needle syringe. A needle guard, including a central needle channel through which the needle fits, incorporates pivotally movable arms which operate to permit the needle to pass through the central channel so as to come to rest in a needle pocket after an injection. Provision of such a needle enclosure for a large hypodermic needle would require a considerable amount of material and add bulk to the needle so as to make the needle difficult to handle. Hagen discloses an alternative embodiment which requires rivet pins and other mechanical features which may make fabrication and use of the device complex and expensive.
Similarly, U.S. Pat. No. 4,795,432 to Karczmer discloses a complex device for providing protection against inadvertent jabs by a hypodermic needle. The Karczmer device comprises various types of springs, tabs and hinged flaps required to effectuate needle stick protection. Like all the prior art discussed above, in addition to being complex, Karczmer cannot be easily adapted or modified for use on needles of various sizes and lengths.
Additionally, none of these devices would be suitable for use on curved needles used in the health care field.